Receive the latest politics updates in your inbox

It took Arlen Specter becoming a Democrat for Democrats to finally beat him.

In Tuesday’s primary in Pennsylvania, Democratic voters ended Specter’s career, something they had been unable to do in five Senate elections, starting in 1980.

Rep. Joe Sestak defeated Specter, who switched parties last year.

Specter spent more than $9 million on the race, nearly three times as much as Sestak.

Campaigning for Specter last September in Pennsylvania, President Barack Obama claimed that “he was a great senator when he was a Republican; he's going to be an even better senator now that he's a Democrat.”

Despite that endorsement, not enough Democrats were persuaded that ex-Republican Specter would be a better Democrat than Sestak.

The presidential endorsement was history was repeating itself. Six years ago, when it looked like Specter might lose the Republican primary to conservative Pat Toomey, President George W. Bush went to Pennsylvania to help push him to a narrow win.

(This year Toomey is the Republican nominee, running against Sestak in November.)

Bush's backing: 'a firm ally'“He's a little bit independent-minded sometimes,” Bush conceded to a GOP rally in 2004. “But there's nothing wrong with that. I can count on this man. That’s important. He's a firm ally when it matters most.” (Sestak used an excerpt of this speech in one of his television ads.)

Specter, 80, has been around long enough to have served as a staff attorney on the Warren Commission in 1964 (where he helped devise the single-bullet theory of President Kennedy’s assassination).

In 1971, President Richard Nixon considered Specter as a Supreme Court nominee. Nixon is heard on a June 4, 1971 Oval Office tape recording favorably comparing Specter with Secretary of State Henry Kissinger.

“He’s got a great future,” Nixon remarked to his aide Bob Haldeman. “He’s a Jew that’s come up like Henry.”

Specter’s longevity explains why some of the Democratic credentials he claims may seem antique to voters under age 65. “I voted for Adlai Stevenson, I voted for him twice; I voted for John F. Kennedy,” Specter told MSNBC’s Chris Matthews last week. Stevenson was the Democratic presidential candidate in 1952 and 1956.

Party switch began his careerSpecter began his electoral career in 1965 by winning election as a reform-minded district attorney in Philadelphia. A Democrat rebuffed by the city’s Democratic political machine, he decided to run as a Republican.

Then he lost four elections: for district attorney, mayor of Philadelphia, and for the Republican nominations for governor and senator.

In 1980 voters rewarded his persistence, giving him his Senate seat.

“No one spends more time traveling the entire length and breadth of the state,” said pollster and analyst Terry Madonna at Franklin & Marshall College in Lancaster, Pa. “No one knows the state better; no one knows more people throughout the state.”

In Pennsylvania’s rural counties, Specter is probably better known for his work as a member of the Appropriations Committee channeling federal money to the state than he is for his role in Supreme Court battles.

He seemed indestructible, both electorally and physically. He has prevailed over lymphatic cancer, heart bypass surgery and a brain tumor.

Battling Bork in 1987 People on the right loathed him for his interrogation of conservative idol Robert Bork, which helped scuttle Ronald Reagan’s Supreme Court nominee in 1987.

“Bork was out of touch with the basic humanitarianism of the law,” Specter later said. Bork did not agree with Specter's view that the Constitution is “a living, growing document.”

Specter’s credibility as an independent who would defy his party made GOP leaders give him the assignment of grilling Anita Hill who accused Supreme Court nominee Clarence Thomas of sexual harassment in 1991.

He called her testimony “flat-out perjury.” But a feminist backlash failed to oust Specter in the 1992 election as he drew an inept Democratic opponent Lynn Yeakel.

With one exception — his quixotic run for the 1996 GOP presidential nomination — Specter has been pragmatic and without illusions.

The pragmatism came through last year when Specter explained his party switch. The polling in Pennsylvania convinced him that “the prospects for winning the Republican primary are bleak” he said.

Specter argued last year that the GOP had shifted so far to the right that he no longer had a home in the party.

But when Bush was president, Specter’s voting record proved that he was firmly aligned with those on the right. The American Conservative Union, the right-of-center advocacy group which rates members of Congress based on dozens of votes on bills of special interest to conservatives, gave Specter a 65 out of 100 rating in 2003, a 75 in 2004, and a 63 in 2005.

Struggle over Judiciary Committee gavel Despite this, conservatives remained wary of him and tried to block him from getting the Judiciary Committee chairmanship in 2004 because he said after Bush won re-election that “I would expect the president to be mindful” of Democratic filibusters that would block any Supreme Court nominee who would vote to overturn the Roe v. Wade abortion decision.

“Sen. Specter needs to satisfy not just us, but all the people who voted for the president on Nov. 2, that he is going to facilitate, and not thwart the president’s judicial nominees,” said Judiciary Committee Republican Sen. John Cornyn of Texas.

Specter survived that uprising. Once he became chairman, his performance gave conservatives every reason to cheer.

In 2006, lawyers at the Federalist Society, the advocacy group for conservative judges, recognized the service Specter had performed for their cause by giving him a warm welcome at their convention.

“I conclude that most of that applause is for Chief Justice Roberts and Justice Alito,” Specter told them. He reminded them that Roberts “is sitting there at age 50, with the prospect of decades of service… Justice Alito is 55.”

The Roberts and Alito victories “may turn out to be the highlight” of Bush’s presidency, Specter said. Bush is gone, Specter is going, but Roberts and Alito will likely remain for many years.